The bluelashed butterflyfish (Chaetodon bennetti) is a reef fish easily recognized by its yellow coloration and the large black spot edged in blue on its sides. It lives in tropical waters of the Indo-Pacific, where it inhabits coral reefs rich in coral colonies.

The bluelashed butterflyfish has a deep, laterally compressed body typical of butterflyfish. Its overall coloration is yellow, with a large round black spot on the sides surrounded by a particularly conspicuous blue edge. Its snout is relatively short.

Juveniles closely resemble adults, but their large black spot has a white outline that gradually disappears as they grow. The bluelashed butterflyfish reaches a maximum length of 7.1 inches.

The bluelashed butterflyfish inhabits tropical waters of the Indo-Pacific, ranging from the eastern coast of Africa to the Pitcairn Islands, and from Japan in the north to Lord Howe Island and Rapa in the south.

In the Indian Ocean, the bluelashed butterflyfish is found in tropical regions along the coast of East Africa and around several islands and archipelagos, including the Mascarene Islands, Seychelles, Maldives, and Madagascar. It is also found in tropical waters of the western and southern Pacific, where coral reefs provide its preferred habitat.

The bluelashed butterflyfish is found on coral reefs and in lagoons rich in corals, at depths of 16 to 98 feet, on reefs close to shore or exposed toward the open sea.

Adults are generally observed alone or in pairs, while juveniles may inhabit Acropora colonies in shallow water. These coral colonies provide them with both shelter and a source of food.

The bluelashed butterflyfish has a varied diet, but coral polyps make up an important part of it, contributing to its close association with coral reefs.

The bluelashed butterflyfish is an oviparous species: the female releases her eggs into the open water, where they are fertilized. Adults form pairs during reproduction.

In butterflyfish, the eggs and larvae are pelagic and drift with ocean currents in the water column, allowing them to disperse over considerable distances before the young fish reach the reefs and settle there.

The bluelashed butterflyfish is listed as many other marine species within The IUCN Red List of threatened species. The bluelashed butterflyfish appears in the IUCN Red List since 2010 within the category Data Deficient !